/Engine/Source/Runtime/Experimental/Chaos/Public/Chaos/ConvexHalfEdgeStructureData.h
The edge index of one of the bounding edges of a plane PlaneIndex must be in range [0,NumPlanes()) PlaneEdgeIndex must be in range [0, NumPlaneHalfEdges(PlaneIndex)) return value is in range [0,NumHalfEdges())
int32 GetPlaneHalfEdge ( int32 PlaneIndex, int32 PlaneEdgeIndex ) const